Inventory Valuation - Using Methods in Java

Open Eclipse or NetBeans and create a Java project with the following details.

For Project Name include: Inventory

For the Main Class include: Inventory

In your Code window, shown below, copy in the program code shown in Figure 1 below, in the appropriate places, except substitute your own name in place of Sammy Student.

PROJECT Inventory Valuation - Using Methods in Java

Figure 1 Source Code for the Inventory Valuation Program

package lab6;

import java.util.Scanner;

//Sammy Student, Programmer

public class Inventory

{

static Scanner sc = new Scanner(System.in);

public static void main(String args[])

{

// begin local variable declaration / initialization zone

char answer = 'Y';

double average = 0.0, cost = 0.0, totValue = 0.0;

int number = 0, sumItems = 0, quantity = 0;

String item = "";

// end local variable declaration / initialization zone

// begin program menu

System.out.println("");

System.out.println("");

System.out.println("***************************");

System.out.println("----Inventory Valuation---");

System.out.println("***(Weighted Average Method)***");

System.out.println("");

System.out.println("");

System.out.println("--------- M E N U ---------");

System.out.println("");

// end program menu

while(answer == 'Y' || answer == 'y')

{

// begin code block for inventory evaluation

System.out.println("number of item types in the inventory ->");

number = sc.nextInt();

for(int i = 1; i <= number; i++)

{

System.out.println("enter the item's description");

item = sc.next();

System.out.println("item description: " + item);

System.out.println("enter item quantity");

quantity = sc.nextInt();

sumItems += quantity;

System.out.println("enter item cost");

cost = sc.nextDouble();

totValue += cost * quantity;

}

// outside the for() loop

PROJECT Inventory Valuation - Using Methods in Java

Figure 1 Source Code for the Inventory Valuation Program ( continued )

average = totValue / sumItems;

// end code block for inventory evaluation

// begin code block to display results

System.out.printf("average cost: $%.2f ", average);

System.out.println("***************************");

// end code block to display results

// begin code block to perform additional program run

System.out.println("run again(Y or N)?");

answer = sc.next().charAt(0);

// end code block to perform additional program run

}

System.out.println("***************************");

}// end main() method

}// end class

STEP 2 Build, Compile and Run the Program

From the menu select [ Run ] and click [ Run Project ] to run your app.

STEP 3 Test the Program

Once you have successfully compiled your program, review the output Console window of your Java editor.

Enter the sample information shown in Figure 2 that follows as a single run.

You can verify your output with this MS Excel formula:

=(5*750+6*3250+10*926)/(5+6+10)

STEP 4 Review the Starter Code Statements

With the starter code running successfully and the output showing similar results to that given in Figure 2 , review the statements that comprise the code.

The starter code has two core program blocks: one to display a menu and another to evaluate the inventory.

In the next few steps you will now segment your program into these two core methods. Separating your program into code blocks or methods assists in having less program statements occupying space in the main() program method.

You will also move some of the local variables in the starter code and make them class - level variables, such that these variables will be recognized and available to all the methods in your program.

PROJECT Inventory Valuation - Using Methods in Java

Figure 2 Initial Test Run

***************************

----Inventory Valuation---

***(Weighted Average Method)***

--------- M E N U ---------

number of item types in the inventory ->

3

enter the item's description

Chair

item description: chair

enter item quantity

5

enter item cost

750

enter the item's description

Computer

item description: computer

enter item quantity

6

enter item cost

3250

enter the item's description

Desk

item description: desk

enter item quantity

10

enter item cost

926

average cost: $1548.10

***************************

run again(Y or N)?

STEP 4 Construct a Method

Locate the following code statements, that were given in the initial starter code.

System.out.println("***************************");

}// end main() method }// end class

As shown below, define a method that will be used to display the program menu.

PROJECT Inventory Valuation - Using Methods in Java

System.out.println("***************************");

}// end main() method

static void displayMenu()

{

// place method body statements below

}// end method

}// end class

Locate the following block of code statements.

// end local variable declaration / initialization zone

// begin program menu

Between the above two comment statements, write the statements below that will call the method that you just created.

// call a method

displayMenu();

You will now move a block of the original start code into the method.

Locate the following block of code that is given in the original code.

// begin program menu

System.out.println("");

System.out.println("");

System.out.println("***************************");

System.out.println("----Inventory Valuation---");

System.out.println("***(Weighted Average Method)***");

System.out.println("");

System.out.println("");

System.out.println("--------- M E N U ---------");

System.out.println("");

// end program menu

Cut this block of code in your original code and paste the block in the body of the method displayMenu() .

PROJECT Inventory Valuation - Using Methods in Java

After you move the code block into the method, run your program and test it again. Did the program run the same as it did before?

STEP 5 Construct Another Method

Locate the following block of code that appears within the current version of your program.

static void displayMenu()

{

// place method body statements below

. . .

}// end method

}// end class

Construct another method named averageCost() , as shown below.

}// end main() method

static void displayMenu()

{

// place method body statements below

. . .

}// end method

static double averageCost()

{

// place method body statements below

. . .

return average;

}//end method

}// end class

Cut the following variable declarations from your current program and place them in your new method, at the top of the methods body.

double average = 0.0, cost = 0.0, totValue = 0.0;

int number = 0, sumItems = 0, quantity = 0;

String item = "";

Also, within the while() loop of your current program, cut these comment

statements and all of the statements that they enclose. Place this group of statements into the new averageCost() method before the return statement.

PROJECT Inventory Valuation - Using Methods in Java

// begin code block for inventory evaluation

. . .

// end code block for inventory evaluation

Finally, modify the output statement in the while() loop to call the method, instead of displaying a variable value.

// begin code block to display results

System.out.printf("average cost: $%.2f ", average);

System.out.println("***************************");

// end code block to display results

The output statement will then look as follows.

// begin code block to display results

System.out.printf("average cost: $%.2f ", averageCost());

System.out.println("***************************");

// end code block to display results

After you move the code block into the new method and modify the output, run your program and test it again. Did the program run the same as it did before?

STEP 6 Construct Even Another Method

You will now create another method as well as create two other variables to help

you modify your display. Your method will calculate the tax on the inventory total cost under the weighted average method by taking the product of the number of items in the inventory and the average cost multiplied by the tax rate.

Use these suggestions to perform this task.

Declare some static ( global ) integer variable. This integer will hold the

number of items that are in the inventory.

Example: static int itemCount = 0; //item count

Declare some static ( global ) double variable. This double will hold the

average inventory cost.

Example: static int averageCost = 0; //average cost

Use these variables in a strategic location to help store a total item count of inventory items as well as the average weighted cost that can be used for your computeTax() function.

Declare a method named computeTax() that will be used to calculate the tax on the inventory. This method should return the resulting tax amount computed as the product of your average cost and item count and tax at a rate of 6 percent. Create an output statement that will include a method call for computeTax() will show a display example statement such as:

" at a level of 133 units, the inventory tax is $ 284.73 . "

PROJECT Inventory Valuation - Using Methods in Java

STEP 7 Submit Your Project

Once you have determined that your modified program is correctly displaying the average cost of the inventory and the tax on the average cost, complete the submission process as follows:

Open MS Word and type a heading for a new document that includes your full name, course number, lab number and date.

Within the document paste in a snapshot of your modified code. Label your snapshot of your modified run with a reasonable description. After your snapshot, paste in your finished source code as well copied in from your Java editor. Submit your MS Word document, when complete.